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diff --git a/src/devices/getting_started.jd b/src/devices/getting_started.jd deleted file mode 100644 index df4fe897..00000000 --- a/src/devices/getting_started.jd +++ /dev/null @@ -1,200 +0,0 @@ -page.title=Overview -@jd:body - -<!-- - Copyright 2010 The Android Open Source Project - - Licensed under the Apache License, Version 2.0 (the "License"); - you may not use this file except in compliance with the License. - You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - - Unless required by applicable law or agreed to in writing, software - distributed under the License is distributed on an "AS IS" BASIS, - WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - See the License for the specific language governing permissions and - limitations under the License. ---> -<div id="qv-wrapper"> - <div id="qv"> - <h2>In this document</h2> - <ol id="auto-toc"> - </ol> - </div> -</div> - -<p>Welcome to the Android Platform Development Kit (PDK) Guide! The Android PDK allows partners to port - their drivers as well as develop, optimize, and test against an upcoming Android platform release. - The Android PDK includes a set of interfaces for the Android hardware abstraction layer (HAL), - platform sources for integration, a binary system image, and HAL and integration documentation. - In addition, the PDK also ships with the Android Compatibility Test Suite (CTS). -</p> - -<h2 id="arch">Android Low-Level System Architecture</h2> -<p>Before you begin porting Android to your hardware, it is important to have an -understanding of how Android works at a high level. Because your drivers and HAL code interact -with many layers of Android code, this understanding can help you find -your way through the many layers of code that are available to you through the AOSP -(Android Open Source Project) source tree as well as the PDK. -The following diagram shows a system level view of how Android works: -</p> - -<img src="images/system-architecture.png"> - -<p class="img-caption"><strong>Figure 1.</strong> Android System Architecture</p> - - <h4>Application framework</h4> - <p>This is the level that most application developers concern themselves with. You should be - aware of the APIs available to developers as many of them map 1:1 to the underlying HAL - interfaces and can provide information as to how to implement your driver. - </p> - - <h4>Binder IPC</h4> - <p> - The Binder Inter-Process Communication mechanism allows the application framework to - cross process boundaries and call into the Android system services code. This basically allows - high level framework APIs to interact with Android's system services. At the application framework level, all - of this communication is hidden from the developer and things appear to "just work." - </p> - - <h4>System services</h4> - <p>Most of the functionality exposed through the application framework APIs must - communicate with some sort of system service to access the underlying hardware. Services - are divided into modular components with focused functionality - such as the Window Manager, Search Service, or Notification Manager. System services are grouped - into two buckets: system and media. The system services include things such as the Window or - Notification Manager. The media services include all the services involved in playing and - recording media. - </p> - -<h4>Hardware abstraction layer (HAL)</h4> -<p>The HAL serves as a standard interface that allows the Android system to call into the device - driver layer while being agnostic about the lower-level implementations of your drivers and hardware. - You must implement the corresponding HAL (and driver) for the particular piece of hardware that your product - provides. Android does not mandate a standard interaction between your HAL implementation and your device drivers, so - you have free reign to do what is best for your situation. However, you must abide by the contract - defined in each hardware-specific HAL interface for the Android system to be able - to correctly interact with your hardware. HAL implementations are typically built into - shared library modules (<code>.so</code> files). -</p> -<h4>Linux Kernel</h4> -<p>For the most part, developing your device drivers is the same as developing a typical Linux device driver. - Android uses a specialized version of the Linux kernel with a few special additions such as - wakelocks, a memory management system that is more agressive in preserving memory, - the Binder IPC driver, and other features that are important for a mobile embedded platform like Android. - These additions have less to do with driver development than with the system's functionality. The PDK - does not provide kernel sources, so you must provide your own. You can use any version of the kernel that - you want as long as it supports the required features, such as the binder driver. However, we recommend - using the latest version of the Android kernel. For the latest Android kernel, see - <a href="{@docRoot}source/building-kernels.html" >Building Kernels</a>. -</p> - - -<h2 id="pdk">PDK Components</h2> -<p>Now that you have a high-level overview of the Android system, we'll go over the PDK and what it provides - to port Android to your product. The PDK provides source files needed to implement - your product and a platform binary that lets you build a runnable system image. You can then install - this barebones image to test your product with the latest builds of Android. The most important source files - included in the PDK are located in the:</p> - - <ul> - <li><code>frameworks/native</code> directory</li> - <li><code>frameworks/av</code> directory for media, camera, DRM, and the audio framework stack</code></li> - <li><code>hardware/libhardware/include/hardware</code> directory for the HAL interfaces </li> - <li><code>vendor/pdk/data/cts</code> directory for the CTS binaries</li> - </ul> -</p> -<p>In addition, the Android PDK includes the following source directories:</p> -<ul> - <li>abi</li> - <li>bionic</li> - <li>bootable</li> - <li>build</li> - <li>device</li> - <li>external (Chromium and Webkit are not included)</li> - <li>hardware</li> - <li>libnativehelper</li> - <li>pdk</li> - <li>prebuilt</li> - <li>prebuilts</li> - <li>system</li> -</ul> - - <p>The PDK also contains documentation that is split into the following sections:</p> - <ul> - <li><a href="{@docRoot}devices/getting_started.html">Getting Started</a> - Explains how to download - the PDK source, how the Android build system works, and how to configure a build for your specific product.</li> - <li><a href="{@docRoot}devices/porting.html">Porting</a> - Explains the various HALs provided by Android - and the interfaces (C header files) that define them. This section also provides reference documentation - for the various HAL interfaces.</li> - <li><a href="{@docRoot}devices/debugtune.html">Debugging and Tuning</a> - Explains the debugging and tuning features of the PDK.</li> - <li><a href="{@docRoot}devices/tech/index.html">Technical Information</a> - Explains important concepts of the Android platform.</li> - </ul> - -<h3 id="cts">Compatibility Test Suite</h3> -<p>CTS binaries for ARM, MIPS, and x86 are provided in the corresponding directories in <code>vendor/pdk/data/cts</code>. Only the ARM - variant is Google-verified as there is no Nexus device running on any other architecture. Not all of the CTS tests since the - complete Android platform is not present. The following CTS tests should work:</p> - -<ul> - <li>android.bluetooth</li> - <li>android.graphics</li> - <li>android.graphics2</li> - <li>android.hardware</li> - <li>android.location</li> - <li>android.opengl</li> - <li>android.openglperf</li> - <li>android.media</li> - <li>android.mediastress</li> - <li>android.nativemedia.sl</li> - <li>android.nativemedia.xa</li> - <li>android.net</li> - <li>android.renderscript</li> - </ul> - <p>You can run individual packages such as <code>android.media</code> with:</p> - <pre>cts-tradefed run singleCommand cts --skip-device-info --package android.media</pre> -</ul> - - <p>Because the PDK is missing many components compared to a full Android source tree, - there is a PDK test plan that is provided with CTS that limits the tests that are ran when using the PDK. You can run - this special test plan with the following command:</p> - - <pre>run cts --plan PDK</pre> - -<p>CTS is always actively under development, so we expect some tests to fail. CTS results - for the Galaxy Nexus are provided for you in the - the <code>vendor/pdk/data/cts/</code> directory and will show which tests fail on that - device. You can safely ignore the failed tests for your devices as well.</p> - - <p>See <a href="{@docRoot}compatibility/index.html">Compatibility</a> for more information on CTS.</p> - -<h2 id="inc-ex">PDK Inclusions and Exclusions</h2> -<p>The PDK is a subset of the complete Android source tree and might be missing things that you might need. Here is a list of what the PDK supports - and does not support:</p> -<ul> - <li>Supports building Android apps using the publicly available, standard SDK. Builds with non-public platform APIs are not supported. The JNI build is supported.</li> - <li>Supports only <code>en_US</code> locale.</li> - <li>Supports only phone layouts. Tablet layouts are not included.</li> - <li>Enables support for software navigation buttons by default, which you can disable by setting <code>qemu.jw.mainkeys=1</code>.</li> - <li>Builds all binaries with SMP (symmetric multiprocessing) features enabled. This might have a small performance impact on non-SMP CPUs.</li> - <li>Includes a minimal amount of Java libraries. Obtain any additional Java libraries from the publicly released Android source tree.</li> - <li>Contains a minimum number of applications. Build and install necessary applications as needed.</li> - <li>Does not support media streaming.</li> - <li>Does not include non-Latin fonts. (set by <code>MINIMAL_FONT_FOOTPRINT</code> variable in <code>BoardConfig.mk</code>). - An app might crash if it requires such fonts. </li> - <li>Does not support replacing framework resources by using the overlay mechanism. - This means all configurations controlled by framework resources are fixed.</li> - <li>Does not support NFC</li> - <li>Does not support DRM</li> -</ul> - -<h2 id="knownissues">Support and Known Issues</h2> -<p> -For questions or to report issues related with the PDK, send a message to the <a href="https://groups.google.com/a/google.com/forum/?fromgroups#!forum/android-pdk-feedback">android-pdk@google.com</a> mailing list.</p> - -<p>The following list describes the known issues with the PDK:</p> -<ul> - <li>After running the CTS (Compatibility Test Suite), <code>android.process.acore</code> crashes. This is caused by -some missing components in PDK and does not affect the operation of CTS tests.</li> -</p> |